There have been many attempts in the past to devise an effective marine harvester for living plants of seaweed of the order Laminariales, i.e. kelp. Most of those previous attempts have resulted in apparatus which either pulls the complete plant from the sea bottom or severs the stalk or stipe of the plant for collection and processing. This is believed to be inefficient and wasteful since the major portion of the kelp plant is the leaf or lamina and, in many species, if only the lamina is severed from the plant it will regenerate a new lamina which will soon be available for harvest. Thus if only kelp laminae were harvested the kelp bed would be harvested again much sooner than if the stipes were severed and new plants were required to establish.
As examples of prior art seaweed or kelp harvesters, reference may be made to British Pat. No. 690,275 (Scottish Seaweed Research Association) of Apr. 15, 1953 which uses a plurality of hooks on an endless belt to engage and tear away the kelp from the sea bottom; and to U.S. Pat. No. 1,120,206 (S. A. Knapp) of Dec. 8, 1914 which uses a band saw arrangement to cut the stalks or stipes. Each of these patents shows apparatus which harvests more than is required and is hence inefficient to the point of representing a questionable investment when applied to kelp of the genus Laminaria or other genera of similar form.
There are some kelps such as the giant bladder kelp harvested off California which grow to the surface of the sea. These plants are harvested by cutting the frond about 4 feet from the surface. In this case there is no problem because new stipes issue from the holdfast which is far removed from the area harvested.